The purpose of this training program is to prepare MD, MD/PhD, or PhD postdoctoral fellows for research careers in the multidisciplinary field of Transfusion Medicine. Since 1985, 35 individuals have participated in this Training Program at the University of Pennsylvania. With few exceptions, all trainees have pursued careers in academic medicine and have continued on in either clinical or basic research having obtained many federal and non-federal grants along the way. Of the 28 who have already completed training, 20 former trainees have become directors or associate directors of academic blood banks and transfusion medicine sections across the country. Because of the many interested, qualified applicants and our successful training record, the program was awarded this T32 training grant beginning in 1994. This has allowed us to provide support for 13 of the 35 individuals. The uniqueness of this program lies in the availability of a broad-based research environment coupled with a well-established clinical Transfusion Medicine training program. This represents one of few such Transfusion Medicine postdoctoral training programs in this country. Research trainees conduct independent research for at least 2 years in the laboratory of an experienced mentor. Mentors are selected among faculty with diverse interests including cell membrane structure/function (red cells, platelets), immunobiology of autoimmune and neoplastic disorders, hematopoiesis and stem cell biology, blood coagulation, virology, and genetic engineering. Opportunities to coordinate trainee research experience with our Transfusion Medicine/Hemostasis Clinical Trial Network is featured in this renewal along with significant emphasis in the area of translational research and cell engineering in which our institution has invested considerable resources. The mentors selected for this program include many senior scientists with extensive experience training postdoctoral fellows and with current, active, interlaboratory collaborations. In addition to investigative work, the Training Program comprises an integrated mix of educational components including didactics, journal clubs, seminars, venues for presentation of trainees' research, as well as a requirement that each trainee participate in one or more teaching opportunities. The program plan includes specific steps for minority recruitment and for the training of MD's with little research experience. Educational programs for trainees in bioethics, grant writing, laboratory safety, and laboratory management are also included. The program's Director and Oversight Committee strive to design an educational experience tailored for each individual trainee.